The display area on a touch sensitive display should be allocated efficiently to allow a user to operate an interface of a touch sensitive device in an intuitive and speedy manner, while at the same time, maximizing use of the available display area for the functions needed by the user. For example, a document viewing area needs to be large enough to see characters, while borders which serve no functional purpose may be removed.
Virtual keyboards can be utilized within an interface having a touch sensitive display (for example, a portable electronic device). Conventionally, a smallest usable size of a virtual keyboard is limited to an area sufficient for containing a particular set of virtual keys, where each of the virtual keys has a smallest usable size that allows a user to both accurately and precisely select a particular virtual key. For example, a virtual QWERTY keyboard having a separate virtual key for each character (e.g., the conventional QWERTY keyboard layout of FIG. 1A) generally occupies about 30 times the minimum area of the virtual key since each key must be a minimum size to be usable. More typically, as shown in FIG. 1B, some space is allocated between virtual keys 25 in a conventional virtual QWERTY keyboard 20, and additional area is allocated for other (e.g., functional) virtual keys 28a-28c. 
Certain conventional virtual keyboards include first and second appearances of virtual keys corresponding to different appearances of the keys before and after making a key selection, respectively, by touching the virtual keyboard within a predetermined key area. A first touch selects a virtual key, and then a second appearance is displayed. For example, FIG. 1C shows the conventional virtual keyboard 20 containing a selected virtual key having a second appearance 35 representing the letter “G.” A conventional second appearance frequently shows a larger and/or otherwise emphasized virtual button containing the same character as in the first appearance. The second appearance 35 allows a user to see the selected virtual key more precisely or easily, while their finger is still touching the device. A final selection is made when the user's finger is removed from the touch sensitive display. However, if a user touches a virtual button and thus initiates a second appearance of the virtual button, the user has the option to move their finger to another virtual button while still touching the touch sensitive display. This allows a user to correct an incorrect selection.
A conventional virtual key can have dimensions of about 4×6 mm, and a conventional virtual keyboard can typically occupy up to about 35-40% (and in some cases up to almost 50%) of the entire touch sensitive display area. For example, FIG. 1D shows a conventional device 100 having a touch sensitive display 110, viewing area 120, virtual keyboard 130, and other virtual keys 140, 150, and 160, in which the virtual keyboard 130 consumes about 35% of the touch sensitive display 110. FIG. 1E shows a conventional device 105 that includes a touch sensitive display 115, viewing area 125, virtual keyboard 135, and other virtual keys 145, 155, and 165. The device 105 has a smaller height-to-width ratio (i.e., aspect ratio) than the device 100 of FIG. 1D, and as a result, the virtual keyboard 135 of device 105 consumes almost 50% of the touch sensitive display 115. Since an average person is more easily able to touch a virtual key of about 1×1 cm with high accuracy and precision, conventional virtual keys can be difficult to accurately and precisely select. Also, dedicating valuable display area to a virtual keyboard can reduce the proportion of display area available for other functions, such as displaying a document or map.
This “Discussion of the Background” section is provided for background information only. The statements in this “Discussion of the Background” are not an admission that the subject matter disclosed in this “Discussion of the Background” section constitutes prior art to the present disclosure, and no part of this “Discussion of the Background” section may be used as an admission that any part of this application, including this “Discussion of the Background” section, constitutes prior art to the present disclosure.